1. Field of the Invention
This invention relates to excavating equipment and more particularly, to a clam bucket attachment for removable cooperation with the crowd and crowd hydraulic cylinder of a conventional backhoe to dig ditches and effect other excavation in the construction industry. The clam bucket attachment of this invention can be adapted to substantially any commercially available hydraulic backhoe, and uses the bucket curl or crowd hydraulic cylinder to open and close a clam bucket which is suspended on one end of a wire cable threaded on a pair of rotatable sheaves which are positioned in the cable boom of the attachment apparatus. The clam bucket attachment is designed to permit the suspended clam bucket to pivot with respect to the backhoe crowd and also to rotate in as much as a 360.degree. circle with respect to the crowd. Alternatively, the rotating function of the clam bucket can be limited and controlled by a small hydraulic cylinder or a reversible electric motor in order to position the bucket in a precise location with respect to the backhoe. The clam bucket attachment is also provided with an outwardly extending cable boom which fits on the end of the crowd and is secured in position, along with a bucket support mechanism, by means of a single pivot pin to facilitate quick and easy installation and removal of the attachment on the crowd of substantially any backhoe.
2. Description of the Prior Art
Clam buckets which are operated by means of drag lines and derricks of varying description are well known in the prior art and have for years been used for such purposes as moving logs, excavation of channels, digging holes for foundations in the construction of buildings and dredging canals. These buckets are provided with hinged mandibles which are controlled by cables extending from the bucket through a system of sheaves in the derrick or crane apparatus and wound on drums which cooperate with the engine of the maachine. An operator controls the operation of the crane boom and drums to effect the desired work using the clam shell to scoop and transport several yards of earth in each digging and lifting sequence.
Similarly, backhoe devices are well known in the prior art and are used for a number of purposes, chief among which is the trenching or excavation for the purpose of laying pipelines, digging foundations and the like. Backhoes are typically provided with rubber tires or tracks, depending upon the specific use to be made of the machine, and are characterized by an extending boom and a crowd which is pivotally attached to the end of the boom, the crowd in turn having a digging bucket pivotally positioned on the end thereof. The boom and crowd are typically operated by hydraulic cylinders which are activated by an operator to effect the desired digging and movement of earth, which is scooped in the bucket. Some backhoes are also provided with a "front end loading" capacity in addition to the bucket device for additional capability in excavating and moving excavated material.
In some instances it is desirable to dig a trench or excavation without traversing the axis of the trench with the machine accomplishing the excavation. This is sometimes necessary due to the close proximity of the trench to an existing structure or forms, or in certain circumstances where it is simply more desirable to have the trenching or excavating equipment in nonalignment with the trench or area to be excavated itself. Under these circumstances it is impossible to use conventional backhoes and trenching devices because such machines depend upon alignment with the traverse of the trench to accomplish the intended purpose. In most instances, backhoes and ditching machines must be aligned with a trench to be constructed in order to dig the trench.
Accordingly, it is an object of this invention to provide a new and improved clam bucket attachment which is capable of cooperating with a conventional backhoe and a conventional clam bucket to effect trenching and excavation work without the necessity of aligning the backhoe with the traverse of the trench or excavation to be accomplished.
Another object of this invention is to provide a clam bucket attachment which can be quickly and easily attached to the crowd of substantially any backhoe and used to excavate from a point or points substantially perpendicular to the traverse line of the excavation to be accomplished.
A still further object of this invention is to provide a clam bucket attachment for backhoes which is capable of being quickly and easily attached to the crowd or curl hydraulic cylinder of the backhoe, and which utilizes a cable boom having two sheaves and a wire cable threaded around the sheaves and a bucket support mechanism to suspend a conventional clam bucket from the cable and bucket support mechanism and effect the desired excavation.
A still further object of the invention is to provide a clam bucket attachment for cooperation with the crowd or bucket curl hydraulic cylinder of a conventional backhoe, which attachment utilizes a wire cable for opening and closing a conventional clam bucket, and which facilitates rotation of the clam bucket in as much as a 360.degree. circle without the necessity of using a hydraulic motor to effect such rotation.
Yet another object of this invention is to provide a new and improved clam bucket attachment for backhoe machines, which can be quickly and easily attached to the crowd of the backhoe by means of a single pin to facilitate pivotal and rotatable suspension of a conventional clam bucket from a boom attached to the backhoe crowd, and operation of the bucket by means of a cable having one end attached to the bucket curl or crowd hydraulic cylinder on the backhoe crowd, and the opposite end attached to the clam bucket to effect excavation by operation of the backhoe crowd and the crowd hydraulic cylinder.
Yet another object of this invention is to provide a clam bucket attachment for backhoes, which attachment includes a boom which is capable of being removably and rigidly attached to the crowd of the backhoe, and a bucket support which is pivotally carried by the backhoe crowd, which boom carries a pair of spaced and rotatable sheaves, around which are threaded a wire cable having one end attached to the crowd hydraulic cylinder of the backhoe, and the opposite end secured to a conventional clam bucket, which clam bucket is both pivotaly and rotatably suspended from the backhoe crowd by means of the boom and the bucket support, and is therefore capable of digging in close places along straight lines and angles and particularly without interference to existing building forms and structures when digging foundation footings.